hello,
does anyone know if there exists a package/function that allows one to find
(numerically) all n roots of a polynomial of degree n, whether they are
real or not? Since NSolve seems to be equivalent to N[Solve], it can not
be used for generic polynomials of fifth degree or higher. Also the
function FindRoot only allows one to find a single root near a given
starting value (which can be complex though).
What I would like, is a function that returns the numerical values of all
n roots as a list of substitution rules, as does Solve or NSolve.
I guess it could be done by successively dividing out a single root found
with FindRoot, but I'd rather first hear if anyone out there already has
a clear-cut solution to this problem.
All answers are appreciated.
Greetings,
Sigurd Schelstraete
University of Gent
Belgium